The invention relates to a gas bag for a vehicle occupant restraint system.
Conventional gas bags comprise an inflation opening, a fabric piece which is arranged inside the gas bag opposite the inflation opening and forms an outflow opening for compressed gas which flows into the gas bag through the inflation opening, and at least one limiting strap which is likewise arranged inside the gas bag.
The fabric piece serves to deflect in a desired direction the hot compressed gas entering into the interior of the gas bag after a gas generator has been activated. This prevents the hot compressed gas from striking directly onto the wall of the gas bag and damaging it. In addition, through the specific deflection of the compressed gas, the unfolding behavior of the gas bag can be influenced to a large extent. According to the direction of inflow of the compressed gas into the gas bag, for example it can be achieved that the gas bag firstly unfolds in lateral direction, in particular upwards and downwards towards the windscreen and towards the floor of the vehicle, and to the vehicle occupant only towards the end of the unfolding process.
The limiting strap serves to influence the shape and the dimensions of the gas bag in particular in the unfolded state. In addition, by means of the limiting strap also the unfolding behavior of the gas bag can be influenced. However, it is a problem that the limiting strap can have a negative effect on the unfolding behavior which is attempted to be maintained by means of the fabric piece.
The invention provides a gas bag in which the limiting strap does not have any negative effect on the unfolding behavior of the gas bag, which is predetermined by means of the fabric piece. According to the invention, a gas bag for a vehicle occupant restraint system comprises an inflation opening and a fabric piece arranged in the interior of the gas bag opposite the inflation opening and defining a volume for compressed gas introduced into the gas bag through the inflation opening. The fabric piece forms at least one outflow opening for the compressed gas. The outflow opening defines a gas exit area affected by the compressed gas flowing through the outflow opening, and comprises at least one limiting strap arranged in the interior of the gas bag but outside of the gas exit area. This ensures that the limiting strap does not lie in front of the outflow opening and thereby does not alter in a disadvantageous manner the outflow speed and the outflow direction of the compressed gas from the volume which is delimited by the fabric piece, for example by the opening being covered.
Advantageous embodiments of the invention will be apparent from the sub-claims.